NCT03141593

Oral Vitamin D Substitution Weekly or Monthly and Adherence

Oral Vitamin D Substitution Weekly or Monthly - Which Procedure Leads to Highest Adherence? A Prospective Intervention Study in Outpatient Care

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 97 (actual)
• Sponsor: University Hospital, Basel, Switzerland · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Vitamin D deficiency (defined as 25(OH)-vitamin D serum level \<50 nmol/l) is cured with supplementation by mouth. National guidelines recommend the administration of 800 IU cholecalciferol daily for an effective treatment, especially during the winter (poor sun exposition). Commercially available pharmaceutical forms are liquid in Switzerland (drops) and solid forms in Germany (tablets and capsules). Because therapeutic range of vitamin D3 is wide and toxicity is seldom reached, even after the consumption of 200'000 IU, and because the administration of 8 drops daily is inconvenient, weekly and monthly administrations of the cumulative amount (i.e., 5'600 IU weekly or 24'000 IU monthly) have been investigated. Both administration schedules are therapeutic equivalent. The study aims to investigate which form (liquid or solid) and which schedule (weekly or monthly) procure the highest adherence behavior with outpatients under polypharmacy i.e., with 4 or more medications daily. The investigators will use commercially available Swiss and German products.

Detailed description

Intervention study in patients with serum vitamin D \<50 nmol/l and polypharmacy, defined as ≥4 medicaments/day. Treatment duration: 6 months. Treatment groups are defined as Lm (liquid monthly 24'000 IU); Lw (liquid weekly 5'600 IU); Sm (solid monthly 20'000 IU) and Sw (solid weekly 5'600 IU). Cross-over design with identical form (liquid or solid) and switching frequence, i.e. from weekly to monthly treatment and vice versa, for 3 months each.

Conditions

• Vitamin D Deficiency

Interventions

Type	Name	Description
DRUG	Vitamin D: liquid form, start weekly	Patient will start treatment with weekly schedule, and switch after 3 months to monthly schedule for another 3 months.
DRUG	Vitamin D: liquid form, start monthly	Patient will start treatment with monthly schedule, and switch after 3 months to weekly schedule for another 3 months.
DRUG	Vitamin D: solid form, start weekly	Patient will start treatment with weekly schedule, and switch after 3 months to monthly schedule for another 3 months.
DRUG	Vitamin D: solid form, start monthly	Patient will start treatment with monthly schedule, and switch after 3 months to weekly schedule for another 3 months.

Timeline

• Start date: 2017-10-09
• Primary completion: 2018-10-31
• Completion: 2018-10-31
• First posted: 2017-05-05
• Last updated: 2020-02-12

Locations

1 site across 1 country: Switzerland